33 results about "Biomedical polymers" patented technology

This invention belongs to the field of biomedical polymer materials technology, and relates to a method for preparing an injectable thermosensitive composite hydrogel that promotes wound healing, and its application. Polyethylene glycol monomethyl ether is used as a macromolecular initiator, and stannous octoate is used as a catalyst to initiate the bulk polymerization of six-membered cyclic carbonate monomers and their derivatives. After polymerization, coupling is performed via hexamethylene diisocyanate to obtain an amphiphilic block polymer with hydrophilic ends and an oleophilic middle. The block polymer is then dissolved in PBS at low temperature, and a certain proportion of wound-healing nanoparticles are uniformly dispersed in the polymer aqueous solution to obtain the injectable thermosensitive composite hydrogel. This composite hydrogel is a viscous liquid at room temperature and has a viscosity of 34°C. o It rapidly gels in environments above °C, meaning that after injection into the body, it can gel quickly and release nanoparticles in situ to promote wound repair. It also possesses excellent wound-healing capabilities.

The invention discloses an antibacterial hydrogel dressing taking spunlace non-woven fabric as a carrier and a preparation method of the antibacterial hydrogel dressing, and relates to the technical field of biomedical polymers. The antibacterial hydrogel dressing is composed of a spunlace non-woven fabric carrier layer and an antibacterial hydrogel functional layer loaded on the surface and in pores of the spunlace non-woven fabric carrier layer, and the preparation method comprises the following steps: sterilizing spunlace non-woven fabric to obtain a spunlace non-woven fabric carrier; adding the antibacterial component into the aqueous solution of the hydrophilic polymer base material to form a hydrogel precursor solution; and immersing the spunlace non-woven fabric carrier into the hydrogel precursor solution, and curing to obtain the antibacterial hydrogel dressing. The antibacterial hydrogel dressing prepared by the preparation method disclosed by the invention has the flexible breathable characteristic of spunlace non-woven fabric and the high swelling and antibacterial functions of hydrogel, has an excellent bactericidal effect on escherichia coli and staphylococcus aureus, can effectively promote healing of infected wounds, is suitable for clinical nursing of burn and traumatic skin injuries, and has wide application prospects. Wide clinical application prospects are realized.

This invention relates to the field of biomedical polymer materials and surface modification engineering, specifically to a posterior scleral reinforcement material and its preparation method. It comprises a polymer matrix and a bioactive modified layer formed by the oxidative crosslinking of a heterobifunctional polymer coupling compound. This copolymer structure includes anchoring groups, hydrophilic linkers, and bioactive groups. Its core principle is to utilize the flexible extension of the hydrophilic linkers to reduce steric hindrance, fully exposing the bioactive groups to the material surface, thereby achieving efficient recognition and binding to integrin receptors. This invention effectively solves the problems of bioinertness of the synthesized polymer matrix and lack of cell recognition sites, achieving a cell proliferation rate more than twice that of the unmodified matrix, demonstrating the material's excellent bioactivity and cell compatibility.

The application of poly(D-lactic acid) and poly(D-lactic acid-glycolic acid) copolymers in constructing micro / nanocarriers for antitumor drugs belongs to the field of biomedical polymer materials and nanomedicine. The antitumor drugs are small-molecule chemotherapeutic agents, small-molecule photosensitizers, small-molecule immunotherapeutic agents, and small-molecule radiosensitizers. The particle size of the poly(D-lactic acid) and poly(D-lactic acid-glycolic acid) copolymers is 10–5000 nm. The effective concentration of the poly(D-lactic acid) and poly(D-lactic acid-glycolic acid) copolymers is 1–500 mg / kg. The antitumor mechanism of the poly(D-lactic acid) and poly(D-lactic acid-glycolic acid) copolymers includes increasing the activity of effector T cells in the tumor microenvironment and increasing the concentration of cytokines such as IFN-γ at the tumor site. In the field of tumor therapy, PLA and PLGA materials composed of D-lactic acid have shown good effects in inhibiting tumor growth, prolonging the survival period of tumor-bearing mice, and activating antitumor immune responses.

This invention discloses a multi-stimulus-responsive upconversion luminescent nanocrystalline magnetic microsphere and its preparation method, belonging to the field of biomedical polymer materials and nanobiotechnology. The microsphere's main body is a porous copolymer matrix, encapsulating a core of magnetite (Fe3O4) magnetic nanocrystals. Rare-earth-doped fluoride upconversion luminescent nanocrystals are coupled to the surface and pores. The copolymer side chains of the microsphere incorporate azide groups, acidic stimulus-responsive groups, and photostimulation-responsive groups, constructing an independent and non-interfering triple orthogonal logic gating system on the surface. The preparation method includes preparing an oil phase containing copolymers, magnetic nanoparticles, and a volatile porogen; pre-emulsifying and homogenizing the oil phase in an acidic aqueous phase using an SPG membrane; inducing phase separation by controlled solvent evaporation to form porous microspheres; and finally coupling the upconversion nanocrystals via a click chemistry reaction. The magnetic microspheres of this invention eliminate background fluorescence interference from complex samples from a physical perspective. Their porous structure endows the microspheres with excellent quasi-levitation properties and magnetic responsiveness, effectively solving problems such as single surface function and signal crosstalk of microspheres. They are suitable for in vitro clinical diagnosis and complex analysis of multiple targets.

The present invention relates to supramolecular biomedical polymers comprising quadruple hydrogen bonding units and to a process for preparing such a supramolecular biomedical polymer and porous biomedical implants thereof. The supramolecular biomedical polymers are particularly suitable for the production of porous biomedical implants that need high strength, elasticity, durability, and slow biodegradation, e.g. medical implants for living tissue regeneration within a mammal, such as the treatment of cardio-vascular diseases, medical prolapses, and hernias.

The invention belongs to the technical field of biomedical polymer materials, and discloses a preparation method and application of alkyl acid modified carboxymethyl chitosan. The preparation method comprises the following steps: (1) activating alkyl acid, EDC and NHS in absolute ethyl alcohol; (2) dropwise adding the activated alkyl acid solution into the carboxymethyl chitosan aqueous solution for grafting reaction; and (3) carrying out precipitation, alkali washing, alcohol washing and drying on the reaction liquid to obtain a target product. Preferably, the alkyl acid is C8-C20 straight-chain alkyl acid, and the dosage of the EDC and the dosage of the NHS are 6-10 times and 3-5 times of the molar weight of carboxyl of the alkyl acid respectively. The invention also provides the alkyl acid modified carboxymethyl chitosan prepared by the method and application of the alkyl acid modified carboxymethyl chitosan in preparation of hemostatic materials. The material has the dual characteristics of rapid liquid absorption and gelation and efficient coagulation promotion, is especially suitable for hemostasis scenes of non-heparinized or heparinized whole blood bleeding, and is simple and convenient in synthesis process and easy for large-scale production.

The invention discloses an injectable hydrogel for enhancing adhesion based on temperature-sensitive driving as well as a preparation method and application of the injectable hydrogel, and belongs to the field of biomedical polymer materials. Raw materials of the injectable hydrogel pre-polymerization liquid for enhancing adhesion based on temperature-sensitive driving comprise a first monomer, a second monomer containing a cross-linking group Y and an adhesion group Z, and a photo-thermal agent. The preparation method of the injectable hydrogel is simple, and a uniform and stable pre-polymerized solution can be formed only by mixing the photo-thermal agent, the temperature-sensitive first monomer, the adhesive functional second monomer and the solvent; then the pre-polymerized liquid is conveyed to a target area in an injection mode to be crosslinked into gel, the adhesion strength of the hydrogel is further enhanced in situ through near-infrared irradiation, the whole process is few in operation steps and short in time consumption, the operation difficulty of industrial production and clinical application can be remarkably reduced, and the application prospect is wide. The problem that injectability and strong adhesion of traditional injectable hydrogel are difficult to consider at the same time is solved.

The invention belongs to biomedical polymer materials, and discloses urethane acrylate and a preparation method thereof, the preparation method comprises the following preparation steps: reacting a hydroxyl monomer with an acryloyl monomer to obtain a methacrylate monomer containing side chain acrylate double bonds; a methacrylate monomer, an initiator and a catalyst are mixed and subjected to a heating reaction to obtain a polymer, then the polymer and a functional monomer are mixed and subjected to a heating reaction to obtain a block polymer, and the functional monomer is used for introducing a disulfide bond into the block polymer; and mixing the block polymer with polyurethane, carrying out heating reaction to obtain a prepolymer, and then adding a photoinitiator for photocuring to obtain the polyurethane acrylate. The polyurethane acrylate prepared by the preparation method has good toughness and light transmittance.

This invention discloses a tough anisotropic hydrogel, its preparation method, and its applications, belonging to the field of biomedical polymer materials technology. The method involves preparing a prepolymer solution using polymer monomers, zirconium salts, and an initiator. After polymerization to obtain an initial hydrogel, the solution is pre-stretched and simultaneously dialyzed in deionized water to achieve equilibration, resulting in a tough anisotropic hydrogel. This method utilizes the synergistic effect of physical pre-stretching and metal coordination bond locking to guide the directional reconstruction of the hydrogel network, thus simply and efficiently preparing a tough anisotropic hydrogel with a stable orientation structure. This hydrogel possesses high strength, high modulus, and high toughness, and also has the ability to guide the directional growth of nerve cells, showing promising application prospects in neural tissue engineering, flexible electronics, and other fields.

This invention discloses a method for preparing UHMWPE profiles, as well as the UHMWPE profiles and their applications, belonging to the field of biomedical polymer materials technology. The preparation method of the UHMWPE profiles enables the UHMWPE profiles to achieve a balance between "high wear resistance" and "high impact resistance." Furthermore, using the UHMWPE profiles to prepare implantable artificial joint materials can ensure the wear resistance required for clinical use while significantly improving the safety margin and long-term reliability of artificial joints under complex stresses.

This invention discloses a GelMA hydrogel-based repair gel for diabetic foot wounds and its preparation method, belonging to the field of biomedical polymer materials and wound repair technology. The repair gel, by weight, comprises GelMA, a photoinitiator, a composite antibacterial agent, embedded growth factors, sodium hyaluronate, an antioxidant, a mechanical modifier, and a pH buffer solvent. This invention constructs a five-pathway synergistic repair system of "antibacterial-antioxidant-anti-inflammatory-promoting angiogenesis-promoting epithelialization," solving the industry pain points of easy inactivation and lack of long-term sustained release of growth factors through liposome encapsulation technology. It can be rapidly photocured in situ on the wound surface, perfectly adapting to irregular foot wounds, and possesses excellent storage stability, light stability, biocompatibility, and controllable degradation. It can significantly improve the pathological microenvironment of diabetic foot wounds and accelerate wound healing.

The application belongs to the technical field of biomedical polymer materials, and discloses in-situ nanofiber materials for enhancing tumor immunogenicity, and a preparation method and application thereof. The application constructs in-situ nanofiber loaded with a degradable carrier, a molecular targeted drug Anlotinib and Gep nanosheet, and then the in-situ nanofiber is made into a patch and directly applied to a tumor lesion, and is combined with NIR assisted irradiation and aPD-L1 treatment. The application not only improves the delivery efficiency of AL through local administration, and overcomes the problem of low efficiency of systemic administration through a nanocarrier, but also takes inhibition of excessive growth of HCC blood vessels as a starting point, combines PTT and ICB treatment, and enhances the immunogenicity of a residual tumor after a three-mode combined treatment cascade, and enhances an immune response. Meanwhile, the application has the advantages of simple components, flexible formula, easy preparation and the like. Therefore, the in-situ nanofiber material has wide practical application value in the field of tumor treatment.

This application discloses an injectable wet-adhesive hydrogel, its preparation method, and its application, belonging to the field of biomedical materials technology. The hydrogel of this application is formed by in-situ covalent cross-linking of liquid component A and liquid component B. Liquid component A contains an aqueous solution of a four-arm polyethylene glycol succinimide ester compound; liquid component B contains an aqueous solution of serum albumin and an amino-containing biomedical polymer additive. Depending on the amino-containing biomedical polymer additive, the hydrogel has two composition schemes: one is a quaternary structure of a four-arm polyethylene glycol succinimide ester compound, serum albumin, polylysine, and sodium alginate; the other is a ternary structure of a four-arm polyethylene glycol succinimide ester compound, serum albumin, and a four-arm polyethylene glycol amine. This hydrogel possesses good injectability and low swelling rate, and can construct a multi-point covalent cross-linking mechanism combining chemical cross-linking and reversible physical cross-linking, significantly improving the wet adhesion performance and mechanical stability of the hydrogel, effectively achieving a long-term stable sealing effect during dynamic tissue activity in vivo.

The invention belongs to the technical field of biomedical polymer materials, and relates to a wound dressing for chronic wounds and a preparation method of the wound dressing. The wound dressing comprises an outer protective layer, an inner protective layer and an inner protective layer which are sequentially stacked from top to bottom, and the outer protective layer is made of a flexible hydrophobic film and used for blocking external pollution; the water-absorbing and water-retaining layer is made of a water-absorbing foam material and is used for absorbing seepage of the wound surface and maintaining a wet environment of the wound surface; the simulated extracellular matrix layer comprises a biocompatible matrix and micro-nano short fibers embedded in the biocompatible matrix, and is used for simulating an extracellular matrix to promote wound healing; the extracellular matrix simulation layer is provided with seepage holes for wound seepage to reach the water absorption and retention layer. The simulated extracellular matrix layer on the surface of the wound dressing simulates a natural extracellular matrix, can guide cell migration and proliferation and does not allow granulation to grow in, seepage holes formed in the simulated extracellular matrix layer allow wound seepage to reach the middle water absorption and water retention layer, and normal humidity of a wound is kept while the seepage is stored in the water absorption and water retention layer.

The application belongs to the field of biomedical polymer materials and regenerative medicine, and particularly relates to an intelligent hydrogel for treating skin tissue damage, a preparation method and a medicine thereof, and application thereof. The intelligent hydrogel comprises a hydrogel support and a functional module. The hydrogel support takes methacrylated gelatin as a matrix and forms a stable three-dimensional network structure through photo-crosslinking. The functional module comprises two core DNA chains, one of which is a ZnR-Cage chain with a sulfhydryl group directly or indirectly connected to one end of the chain, and the other is a CD44-link chain. The two chains form a non-active assembly through base complementary pairing. The intelligent hydrogel has many advantages such as strong spatiotemporal controllability, overcoming drug burst defects, efficient cascade repair, realizing targeted synergistic treatment, efficient integration, excellent stability and clinical transformation potential. It is particularly suitable for clinical treatment of complex wounds such as diabetic ulcers and infected wounds.

The invention relates to the technical field of biomedical polymer materials, and discloses a preparation method of an artificial pulmonary membrane material. The method comprises the following steps: mixing vinyl-containing polydimethylsiloxane, a sulfydryl-containing silane monomer, a sulfonate group-containing functional monomer, a rhodamine lactam structure-containing early warning functional monomer and a hydrogen-containing silicone oil cross-linking agent to prepare a precursor solution; coating a microporous support membrane with the precursor solution, heating and curing, so that each functional monomer is integrated into a polymer network through covalent bonds; and finally, carrying out an in-situ nitrosation reaction, and converting the immobilized sulfydryl into S-nitroso mercaptan. According to the invention, functional units are stably immobilized in the form of covalent bonds, so that the problems that the existing physical coating is easy to fall off and the anticoagulant performance is quickly attenuated are solved. The prepared material can synergistically release nitric oxide and realize lasting anticoagulation by utilizing fixed negative charges, and the integrated fluorescent unit can also respond to local pH drop in the initial stage of thrombus, so that the material is endowed with in-situ real-time early warning capability for failure risk.

The present application relates to a kind of gynecological suture operation based on high-performance biomedical polymer material suture needle and thread kit and matching method, manufacturing method, to solve the problem such as insufficient suture line supporting force, easy to cut tissue and needle hole leakage in gynecological operation, manufacturing method uses specific specification polyester fiber, by the independent tension control of warp yarn, and using flat-end shuttleless loom weaving and high-temperature long-time heat setting, it is made into flat suture line with low elongation and high form stability.The tail end of suture needle in kit is provided with radially compressed closure lateral open, for from side and clamp the flat suture line.The needle body diameter of suture needle and the effective filling diameter of flat suture line under stress match, realize the close closure of needle hole.The scheme of the present application can provide reliable long-acting tissue support, reduce tissue damage, prevent leakage, improve the safety and convenience of overall operation, improve the clinical effect of gynecological operation, especially cervical cerclage.

This invention belongs to the field of biomedical polymer materials. Specifically, it relates to an injectable dual-network hydrogel, its preparation method, and its application in long-term prevention of postoperative tissue adhesion. The hydrogel consists of two interpenetrating three-dimensional cross-linked networks: one is a polysiloxane network formed by the condensation polymerization of γ-aminopropyltrialkoxysilane; the other is a hyaluronic acid network formed by the cross-linking of thiolized hyaluronic acid through dissolved oxygen oxidation under the catalysis of amino groups in the polysiloxane network. The two networks interpenetrate to form a stable three-dimensional cross-linked structure. Compared with existing anti-adhesion materials that struggle to balance biocompatibility, wet tissue adhesion, and long-term stability, the hydrogel of this invention exhibits good biocompatibility, wet tissue adhesion performance, a slow degradation rate, and injectability. It can be used as a medical barrier material for the prevention of postoperative tissue adhesion, especially suitable for long-term anti-adhesion applications after abdominal and pelvic surgeries.

The invention relates to the field of biomedical polymer materials, in particular to active shrinkage hydrogel based on a red light carbon dot photosensitizer and a preparation method and application of the active shrinkage hydrogel. The active shrinkage hydrogel is prepared from the following raw material components in parts by mass: 100 parts of N-alkyl substituted acrylamide and derivatives thereof; 10 to 30 parts of anionic polysaccharide; 0.5 to 2 parts of a bisacrylamide compound; 0.5 to 2 parts of a tertiary amine compound; 0.5-2 parts of a free radical initiator; and 1-200 parts of a red light carbon dot photosensitizer. The hydrogel disclosed by the invention can generate remarkable mechanical shrinkage in the interval of 32-40 DEG C and actively release a red light carbon dot photosensitizer, the released red light carbon dot photosensitizer efficiently generates active oxygen 1O2 under the irradiation of visible light, and the bacteriostasis rate on broad-spectrum pathogens such as staphylococcus aureus, escherichia coli and candida albicans is greater than 99%. The preparation method provided by the invention has the characteristics of simple and convenient process, low cost and suitability for large-scale production, and provides an intelligent, efficient antibacterial and healing-assisting dressing material for clinical wound management.

This invention belongs to the field of biomedical polymer hydrogel technology, and specifically relates to a photosensitive and thermosensitive hybrid rapid hemostatic hydrogel. The hydrogel components of this invention include poly(N-isopropylacrylamide) grafted modified gelatin, poly(N-isopropylacrylamide) modified hyaluronic acid, quaternized gelatin, photoresponsive molecule-modified hyaluronic acid, and photoinitiator LAP. Due to the presence of modified gelatin and hyaluronic acid, the hydrogel can effectively improve its adhesion to bleeding wounds and achieve effective hemostasis; the modified molecules used have photosensitive or thermosensitive environmental responsiveness, and by applying specific conditions, the curing speed of the hemostatic hydrogel can be accelerated, preventing the hydrogel components from being washed away by blood, thus enabling rapid wound hemostasis.

This invention belongs to the field of biomedical polymer materials, and relates to pH / GSH spatiotemporal cascade-responsive antitumor nanomedicines, their preparation methods, and applications. The pH / GSH spatiotemporal cascade-responsive antitumor nanomedicines are formed by the self-assembly of polymer prodrugs with the structure shown in formula (1). The pH / GSH spatiotemporal cascade-responsive antitumor nanomedicines provided by this invention can highly sensitively identify and respond to the extremely narrow pH change window of the tumor microacid environment, achieving charge reversal on the nanomedicine surface and thus enhancing the cellular uptake efficiency of the nanomedicine. Subsequently, in response to the highly expressed GSH within the cells, it precisely releases the drug at specific points, killing tumor cells. Based on the dual significant characteristics of the acidic pH and GSH in the tumor microenvironment, this invention significantly improves the cellular uptake efficiency of the drug through a spatiotemporal cascade response mechanism of "pH-triggered charge reversal - GSH-induced controlled drug release," while simultaneously achieving precise and controllable drug release, effectively inhibiting cancer cell growth. This provides a general-purpose nanomedicine platform for solid tumor treatment that is structurally controllable, has excellent synergy, and possesses both basic research value and clinical translational potential. Formula (1)

This invention discloses a natural polysaccharide hydrogel loaded with platelet-rich plasma, its preparation method, and its applications, belonging to the field of biomedical polymer materials. It includes chitosan derivatives, aldehyde-modified natural polysaccharides, and platelet-rich plasma. The hydrogel network is a dynamic cross-linked network, comprising a Schiff base-based dynamic cross-linked network formed by the amino groups in the chitosan derivatives and platelet-rich plasma with the carboxyl groups of the aldehyde-modified natural polysaccharides. The raw materials used in this invention, chitosan derivatives and aldehyde-modified natural polysaccharides, are both natural polysaccharides with good biocompatibility. The aldehyde-modified natural polysaccharides can promote tympanic membrane healing. The platelet-rich plasma is extracted from autologous blood, avoiding immune rejection and reducing the probability of infection. Furthermore, it contains various high concentrations of growth factors that promote cell proliferation and differentiation, thus promoting cell growth and inhibiting inflammation.

The invention belongs to the field of biomedical polymer materials, and discloses a preparation method and application of an epitope imprinting bionic receptor for self-recruitment of endogenous osteogenic growth peptide. According to the invention, from the angle of collection of endogenous growth factors, the OGP is taken as a target molecule, the epitope imprinting polymer nanoparticles MIP with specific recognition capability are prepared by adopting an epitope imprinting technology, and specific capture of the endogenous OGP is realized. Further, according to the invention, the MIP is introduced into a polyethylene glycol PEG hydrogel system, and the epitope imprinting bionic receptor MIP (at) PEG capable of collecting endogenous osteogenic factors is prepared. Directional capture and slow release of OGP and activation of local osteogenesis signals are realized in vivo, and formation of new bones in a bone defect area is remarkably promoted. The invention provides a new thought and experimental basis for developing a novel tissue engineering scaffold based on endogenous growth factor recruitment, and has important clinical application prospects.

The application discloses a hydrogel-based adhesive for adhesion of various substrates and a preparation method and application thereof, and relates to the technical field of biomedical polymer materials. Raw materials include the following components in parts by weight: 80-150 parts of monomer two, 20-200 parts of tannic acid, 280-400 parts of acrylic acid, 20-200 parts of a first initiator, 2-20 parts of a crosslinking agent, 220-300 parts of a thickening agent, and 800-1000 parts of a solvent. The application selects tannic acid and acrylic acid as an adhesion main body, and the tannic acid is used as a kind of mussel biomimetic adhesion unit, and has good adhesion to various substrates. The internal dynamic bond formed by the tannic acid and the acrylic acid can make the adhesive self-heal after tearing, cutting and the like, and the dynamic bond promotes the crosslinking between polymer chain segments, thereby strengthening the stability of the overall structure.

The invention discloses degradable and elastic embolism microspheres with uniform particle size as well as a preparation method and application of the embolism microspheres, and belongs to the technical field of biomedical polymer materials. Crosslinkable micromolecules with an acrylic acid structure are connected to the macromolecules in a covalent bond mode, and the functionalized macromolecules are formed. The embolism microspheres are prepared through microfluidic and free radical polymerization technologies, and the microspheres prepared by the method have good application prospects in the field of arterial embolism treatment. According to the embolism microsphere, the embolism microsphere with the uniform particle size is prepared through the microfluidic technology, the generation operation is further simplified, the production cost is reduced, and the production process is more economical and environmentally friendly. The embolism microsphere disclosed by the invention is high in safety, convenient to prepare, good in dispersity, relatively good in elasticity and good in embolism effect, has relatively large transformation potential in the aspect of transarterial embolism treatment, and is expected to assist the development of vascular embolism agents.

This invention relates to the field of biomedical polymer materials technology, specifically to a polyethersulfone-based material with blood purification and anticoagulation functions, its preparation method, and its applications. The polyethersulfone-based material uses polyethersulfone as the main component, and a stable multi-coordination network structure is constructed by introducing terpyridine ligands and multivalent metal ions at the molecular level. Furthermore, the anticoagulant active molecules argatroban or heparin are immobilized on its surface, achieving selective adsorption of blood toxins and synergistic regulation of the anticoagulation reaction. The material is prepared using a process combining phase inversion membrane formation technology and surface coordination modification, resulting in a composite interface on the membrane surface rich in hydrophilic groups and a stable anticoagulant layer, significantly improving blood compatibility and membrane flux stability. This composite membrane can simultaneously perform purification and anticoagulation functions in hemodialysis, hemofiltration, and extracorporeal circulation systems, exhibiting good mechanical strength, chemical stability, and biosafety. The preparation route of this invention is simple, the parameters are controllable, and it is suitable for large-scale production.

This invention belongs to the field of biomedical polymer materials technology, and discloses a polylactic acid-gelatin composite modified material and its preparation method and application. The preparation method includes the following steps: (1) dissolving polylactic acid to obtain a polylactic acid solution; dissolving gelatin to obtain a gelatin solution; (2) adding the gelatin solution to the polylactic acid solution to obtain a mixture; (3) adding a crosslinking agent to the mixture, reacting to obtain a blend; (4) injecting the blend into a mold and freeze-drying to obtain the polylactic acid-gelatin composite modified material; the gelatin is selected from type A gelatin or type B gelatin; the crosslinking agent is 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and / or N-hydroxysuccinimide; the mass ratio of polylactic acid to gelatin in the mixture is 60-95:(5-40). The obtained polylactic acid-gelatin composite modified material simultaneously meets the requirements of good mechanical properties and degradation performance, and the degradation performance can be controlled.

This application relates to the field of biomedical polymer materials technology, and discloses a variable-rigidity chest drainage tube based on a stimulus-responsive hydrogel and its preparation method. The variable-rigidity chest drainage tube comprises an interpenetrating network hydrogel, which includes: a chitin first network, prepared by phase inversion from a chitin solution with a mass percentage concentration of 1.5-4.0%; and a polyacrylamide second network, formed by polymerizing a second network precursor solution in the first network. The second network precursor solution comprises: 15-30% w / v acrylamide; 0.1-1.0% w / AAm N,N'-methylenebisacrylamide; and 0.5-2.0% w / AAm ammonium persulfate. This invention utilizes the reversible reconstruction mechanism of hydrogen bonds between the chitin and polyacrylamide networks to maintain high rigidity of the drainage tube before insertion and transform it into high flexibility after placement in body fluid, thus solving the patient discomfort and tissue damage risks caused by excessive rigidity of silicone tubes.

The application relates to the technical field of biomedical polymer imaging materials, and discloses a thermoplastic polyurethane imaging composite material as well as a preparation method and application thereof.The raw material components of the thermoplastic polyurethane imaging composite material include thermoplastic polyurethane, modified imaging agents and additives; wherein the modified imaging agents are obtained by the reaction of a modifier and an imaging agent; the modifier includes a reactive silane coupling agent and a flexible high-molecular-chain compound, the flexible high-molecular-chain compound contains hydroxyl groups or carboxyl groups on a molecular chain, the hydroxyl groups or the carboxyl groups can chemically react with organic functional groups in a molecular structure of the reactive silane coupling agent or form hydrogen bonds, and the number-average molecular weight of the flexible high-molecular-chain compound is 300-3000.The preparation method is clear in steps and controllable in conditions, and the prepared thermoplastic polyurethane imaging composite material has excellent X-ray imaging properties, a high mechanical property retention rate and good processing fluidity.